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Because the results of the nutritional status released by Chilean institutions which collect anthropometric data on their population under control, show different increments in the prevalence of obesity between preschoolers and children in 1st grade, we decided to verify the real magnitude of this increase. This study is based on a longitudinal investigation which began in 2006 and included 1100, three-year old children, which we evaluated when they were 4, 5 and 6 y. The nutritional status was determined according to BMI Z and WHO References 2006/2007. The information was also used to determine the concordance between the anthropometric data collected on first graders by teachers from public schools in 2009 (JUNAEB data set) and the same children assessed in parallel by INTA (INTA data set). The sample included 474, six-year olds. No differences were found between the average BMI Z and HAZ of the two data sets, and the degree of concordance between the BMI Z's was good (rho = 0.73), however there were differences in the nutritional status, since the prevalence of low weight was significantly greater when assessed with JUNAEB's data (9.5% vs. 3.6% ), while that for obesity was lower with INTA's data, 17.5% vs. 19.2% (not significantly different). At 4 and 5 y, obesity prevalence of the children was 13.3% and 15.7% respectively (INTA's data). Considering the observed nutritional trajectory, it is likely that the rise in obesity between 4 and 6 y of age, was 4 percentage points and not 6, as was determined with INTA's data.  相似文献   
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研究了在酸性条件下从豆腐加工废水中提取高纯度多糖,水溶性多糖和大分子量多糖的提取条件以及水溶性多糖和大分子量多糖的胶凝作用,乳化特性和单糖组成。结果表明,大分子量多糖产生于提取过程中,水溶性多糖由阿拉伯半乳聚糖组成,一些多糖组成在提取过程中分解成木糖和鼠李糖,高纯度多糖的纯化性能和乳化稳定性比水溶性多糖高。  相似文献   
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Effect of residual stress generated during tube fabrication, roll expansion and machining of stainless steel on the stress corrosion cracking (SCC) susceptibility was studied by testing fabricated tubes, tube–tube sheet joint and heavily machined plate of austenitic stainless steel (SS) in boiling MgCl2. U bend samples of machined plate were exposed to acidified SO4 + Cl? environment at room temperature to study its ambient temperature SCC behavior. The results correlate the SCC behavior of the SS tubes and roll expanded joints to the nature and magnitude of residual stresses present. The study also highlights the distinct difference in ambient temperature SCC behavior of machined vs. nonmachined surfaces.  相似文献   
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Mucin type O-glycans with core 2 branches are distinct from nonbranched O-glycans, and the amount of core 2 branched O-glycans changes dramatically during T cell differentiation. This oligosaccharide is synthesized only when core 2 beta-1, 6-N-acetylglucosaminyltransferase (C2GnT) is present, and the expression of this glycosyltransferase is highly regulated. To understand how O-glycan synthesis is regulated by the orderly appearance of glycosyltransferases that form core 2 branched O-glycans, the subcellular localization of C2GnT was determined by using antibodies generated that are specific to C2GnT. The studies using confocal light microscopy demonstrated that C2GnT was localized mainly in cis to medial-cisternae of the Golgi. We then converted C2GnT to a trans-Golgi enzyme by replacing its Golgi retention signal with that of alpha-2,6-sialyltransferase, which resides in trans-Golgi. Chinese hamster ovary cells expressing wild type C2GnT and the chimeric C2GnT were then subjected to oligosaccharide analysis. The results obtained clearly indicate that the conversion of C2GnT into a trans-Golgi enzyme resulted in a substantial decrease of core 2 branched oligosaccharides. These results, taken together, strongly suggest that the predominance of core 2 branched oligosaccharides in those cells expressing C2GnT is due to the fact that C2GnT is located earlier in the Golgi than alpha-2,3-sialyltransferase that competes with C2GnT for the common substrate. Furthermore, alteration of Golgi localization renders the chimeric C2GnT much less efficient in synthesizing core 2 branched oligosaccharides, indicating the critical role of orderly subcellular localization of glycosyltransferases.  相似文献   
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A rollback recovery scheme for distributed systems is proposed. The state-save synchronization among processes is implemented by bounding clock drifts such that no state-save synchronization messages are required. Since the clocks are only loosely synchronized, the synchronization overhead can be negligible in many applications. An interprocess communication protocol which encodes state-save progress information within message frames is introduced to checkpoint consistent system states. A rollback recovery algorithm that will force a minimum number of nodes to roll back after failures is developed  相似文献   
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Research and policy argue for more compact cities to respond to sustainable development challenges. However, what actually needs to be made more compact and how, is under examined, particularly in global South cities where north notions of urban qualities are adopted without being questioned. Informed by a qualitative study in informal and compact neighborhoods in Havana, this paper explores which qualities are important to deliver more just cities, and what strategies are developed by residents to strengthen beneficial qualities and address detrimental qualities in contexts of informal urbanization and compactness. It shows how the street, human capital, neighborhood, housing affordability, citizenship and vibrancy are significant compact city qualities neglected in the literature. Finally, the paper shows how diverse strategies are developed by residents to draw upon these qualities, such as self-help urbanism, learning and innovation, economic entrepreneurship, networks of solidarity, economies of reciprocity, local imaginaries and active citizenship.

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